Merge "Update default image for n preview docs. Update tools resources." into mnc-mr-docs
am: 0a957d5aa2

* commit '0a957d5aa28920f8854070676955f941e3ae6726':
  Update default image for n preview docs. Update tools resources.

Change-Id: I3fa206d3bfc74d20cb74e19f0d084d62fb47c0e2